Apparatus and method for crimping yarn



SEPL 2, 1969 MclNTYRE 3,464,096

APPARATUS AND METHOD FOR CRIMPING YARN 3 Sheets-Sheet 1 Filed Oct. 15, 1966 Sept. 2, 1969 R. M INTYRE 3,464,096

APPARATUS AND METHOD FOR CRIMPING YARN 3 Sheets-Sheet 2 Filed Oct. 15, 1966 Sept. 2, 19 69 Mcl TYRE 3,464,096

APPARATUS AND METHOD FOR CHIMPING YARN Filed Oct. 5, 1966 5 Sheets-Sheet 3 FIG. 6.

M Ma United States Patent M 3,464,096 APPARATUS AND METHOD FOR CRIMPIN-G YARN Ronald McIntyre, Rochdale, Lancashire, England, assignor to The Klinger Manufacturing Company Limited, London, England, a British company Filed Oct. 3, 1966, Ser. No. 583,642 Claims priority, application Great Britain, Oct. 23, 1965,

rm. Cl. noz 1/00 US. Cl. 281.7 13 Claims ABSTRACT OF THE DISCLOSURE Yarn crimping apparatus in which crimped yarn' is drawn oil by winding means from the leading end of a plug of crimped yarn advancing through a passage into which yarn has been fed and longitudinally compressed includes means for varying the rate of operation of the winding means so as to maintain the leading end of the plug in a predetermined range of position. The means includes a switch controlling the rate of operation of the winding means and actuating means for the switch arranged to be operated by the yarn being drawn otf changing its position consequent upon the leading end of the plug moving beyond the predetermined range of position.

This invention relates to apparatus for crimping yarn of the kind in which there is provided means for feeding the yarn into a passage arranged to restrict its rate of travel, thereby compressing the yarn along its length to form a plug which fills the passage as it moves through the passage; the yarn, which is in a crimped state in the plug, then being set and withdrawn from the leading end or head of the traveling plug and wound on to a package or bobbin. More particularly the invention relates to such apparatus including means for varying the rate of withdrawing and winding the crimped yarn.

It has been proposed to provide a serrated wheel for moving the plug of yarn through the passage, the periphery of the wheel extending into an arcuate groove so as to leave a clearance between the wheel and the bottom of the groove. In this case the yarn is fed into the groove and the plug is formed within the clearance between the wheel and the groove. The yarn is then withdrawn from the end of this plug through a slot which extends outwardly from the bottom of the groove. Should the end of the plug move backwardly or forwardly in the passage to such an extent that it is not alongside the withdrawal slot, considerable difficulty can arise in withdrawing the yarn. Thus, in the former case the tension in the withdrawing yarn may increase sufiiciently to cause the yarn to break, and in the latter case the withdrawing yarn may become tangled with the plug.

In United States patent specification No. 3,174,206 there is disclosed, inter alia, photo-electric means for detecting the position of the leading end of the travelling plug in the arcuate passage, and controlling the rate at which the yarn is wound onto the package or bobbin from the plug in accordance with said position.

Whilst the photo-electric means satisfactorily controls 3,464,096 Patented Sept. 2, 1969 the rate of withdrawal of yarn from the traveling plug under most circumstances, it has been found that where the electricity supply for the device is liable to considerable voltage variation, the high voltage sensitivity of the photo-electric means can possibly lead to incorrect control of the package or bobbin wind rate.

Accordingly, it is an object of the present invention to provide apparatus for crimping yarn including improved means for controlling the rate of withdrawal of the crimped yarn from the leading end or head of the plug so that the extent of forward or rearward movement of said leading end or head relative to said passager is limited.

According to one aspect of the invention there is provided an apparatus for crimping yarn including means for feeding the yarn into a passage, means for restricting the rate of travel of the yarn through the passage so that it is compressed along its length to form a plug of crimped yarn, winding means for drawing off the crimped yarn from the leading end of the plug through an exit from the passage, switch means operatively connected with said winding means, switch actuating means connected to said switch means and disposed between said exit from the passage and said winding means, said actuating means being so located with respect to the exit from said passage that when the leading end of the plug moves beyond a predetermined limit in the passage the withdrawing yarn causes said switch actuating means to actuate the switch means to vary the rate of drawing off the crimped yarn through said exit and thereby restore the position of the leading end of the plug within said predetermined limit.

The means for restricting the rate of travel of the yarn through said passage may comprise a wheel having a serrated periphery. The periphery of said wheel may project into an arcuate groove in said passage which circles said wheel and along which groove the plug of crimped yarn travels with said wheel.

The switch actuating means may comprise a switch actuating member engageable with the withdrawing yarn, the switch actuating member being caused to move by the withdrawing yarn beyond a predetermined position whenever the leading end of the plug moves beyond said predetermined limit so that the switch actuating member actuates the switch means to vary the rate of drawing off the crimped yarn.

The switch actuating member may be arranged to actuate said switch means whenever said member is caused to move beyond a second predetermined position displaced from the first mentioned predetermined position, the second predetermined position corresponding to movement of the leading end of the plug of yarn in said passage to a second predetermined limit, whereby the switch means is actuated to vary the rate of drawing off the yarn whenever the leading end of the plug moves to either the the plug is respectively positioned beyond predetermined forward and backward limits in the passage, and thereby restore the leading end of the plug between said predetermined forward and backward limits.

Each of said actuating members may comprise an arm and a pin mounted transversely at the end portion of said arm, the other end of said arm being connected to one of said switch means, the actuating members being so arranged that when the leading end of the yarn plug moves forwardly or backwardly in the passage beyond said predetermined limits, the withdrawing yarn impinges on one or other of said pins, thereby turning the respective lever and actuating the respective switch to vary the rate of rotation of the winding means.

The apparatus may include a variable speed electrical drive motor coupled to said winding means, and an electrical circuit for energising said motor, which circuit has connected therein said first and second switches arranged on operation to vary the energisation of the motor and hence its speed.

The arrangement of the motor operating circuit may be such that one of the switches is normally urged closed and the other is normally urged open, the normally closed switch being opened by said withdrawing yarn when the leading end of the plug moves backwardly in the passage to one of said limits, thereby placing the motor in a slower operating mode so that the leading end of the plug advances along said passage. In this latter case the switch actuating members may be spring urged in a non-actuating direction, but be so arranged and weighted that the first switch actuating member is normally held by gravity against the action of the spring in the actuating position, whilst the second switch actuating member is held by its spring against gravity in the nonactuating position. This may be achieved, for example, by arranging the first actuating member horizontally so as to provide the maximum moment of its weight against its spring, but by arranging the second actuating member at an inclination to the horizontal such that the moment of its weight acting against its spring is insufficient to cause actuation of the switch.

Alternatively, the electrical circuit may include three energising circuits for causing the motor to rotate at three respective speeds, the motor being rotated at a high speed when the withdrawing yarn impinges said first actuating member, a low speed when the yarn impinges said second actuating member and otherwise at an intermediate speed.

Said first and second switches may comprise first and second microswitches.

In one embodiment of the invention there is provided an apparatus for crimping yarn including means for feeding the yarn into a grooved arcuate passage, a serrated wheel for restricting the rate of travel of the yarn through the passage so that the yarn is compressed along its length to form a plug of crimped yarn, the plug of crimped yarn travelling in the groove in the passage with said wheel, winding means for drawing off the crimping yarn from a leading end of the plug through an exit from said passage, switch means operatively connected with said winding means, switch actuating means connected to said switch means and being so located with respect to said exit that when the leading end of the plug moves beyond a predetermined limit in the passage the withdrawing yarn impinges said switch actuating means to actuate the switch means to vary the rate of rotation of the winding means and thereby restore the position of the leading end of the plug within said predetermined limit.

According to another aspect of the invention there is provided a method of crimping yarn comprising feeding yarn into a passage to form a plug, engaging the plug of yarn and conveying the plug to an exit end of the passage, withdrawing the yarn from the leading end of the plug as it is being conveyed, and controlling the rate of withdrawal of the yarn in dependence on the posi- 4 tion of the yarn withdrawing from the exit whereby to vary the withdrawal rate to maintain the leading end of the plug in the passage within predetermined limits.

In order that the invention may be more readily understood, embodiments thereof will now be described by way of example with reference to the accompanying drawings in which:

FIG. 1 is an elevation partly in section of a portion of one embodiment of yarn crimping apparatus according to the invention showing the manner in which the microswitches are arranged in relation to the yarn crimping apparatus;

FIG. 2 is an enlarged view of a portion of FIG. 1;

FIG. 3 is a perspective view of a portion of FIG. 1;

FIG. 4 illustrates one embodiment of an electrical circuit by means of which the microswitches control the driving motor of the winding means.

FIG. 5 illustrates another embodiment of an electrical circuit by means of which the microswitches control the driving motor of the winding means;

FIG. 6 is a schematic illustration of a crimping apparatus according to FIGS. 1 to 4 or 1 to 3 and 5 in combination with winding means.

In FIGS. 1 to 3 of the drawings, there is illustrated a yarn crimping apparatus in which the yarn 1 is shown being drawn upwardly by two rollers 2 and 3 (not shown in FIG. 3) which are driven in opposite directions and between which the yarn is gripped.

The rollers 2 and 3 are disc-like in form and project into intersecting recesses on opposite sides of a block 4, which is secured to the lower end of an electrically heated arcuate element 5. The inner face of the element 5 is provided with an arcuate groove or passage 6, in which part of the serrated periphery of a wheel 7 rotates.

A clearance is provided between the bottom of the groove and the circumference of the wheel to define a crimping chamber. The block 4 is provided with a passage 8 (see FIG. 3) which extends up from a gap between the upper sides of the two rollers 2 and 3 leading into the arcuate groove 6 near the end thereof. The serrated wheel 7 is fixed to a shaft which is rotated by any appropriate transmission system such as that described in the aforementioned patent specification No. 3,174,206.

Fixed to the upper end of the arcuate element 5 is an extension 10 which has an arcuate groove 11 formed in the inner face thereof, which groove is an extension of the groove 6. The yarn is fed into the crimping chamber and a plug 12 of zig zag crimped yarn is built up in the crimping chamber. The plug 12 is conveyed through the passage between the periphery of the serrated wheel 7 and the bottom of grooves 6 and 11 by the teeth 13 which engage the plug for this purpose.

The rates of the feeding of the yarn into the crimping apparatus and of the rotation of the wheel 7 are desirably so chosen with respect to the rate of winding of the crimped yarn as to maintain the end of the plug from which the yarn is withdrawn at as near to a fixed position as possible. However, due to various factors the leading end of the plug tends to move forwardly or backwardly within the passage from a desired median position.

The yarn is drawn off the head of the plug 12 through an arcuate slot 14 in extension 10, and then passes through a guide 15 from which the yarn is fed to a winding bobbin (not shown).

Should for any reason the yarn not be drawn away quickly enough from the leading end or head of the plug 12, it could be carried round by the wheel 7 to enter again the groove 16 causing the mechanism to become clogged, and should the crimped yarn be drawn away too quickly from the leading end of the plug it could break. Thus, it is important that the rate of withdrawal of the yarn from the leading end or head of the plug should bear an accurate relationship to the position of the plug of yarn within the passage.

Accordingly, as is shown in FIGS. 1 and 3 microswitches 17 and 18 are provided to control, in a manner described hereinafter, the position of the leading end of the plug within the passage.

According to the rate at which the yarn is drawn away from the leading end of the plug, the leading end of the plug will advance through the passage so that the withdrawing yarn 19 will contact and press upon a pin 20 as is the condition shown in FIG. 1. Alternatively, the head of the plug 12 will move along the passage so that the withdrawing yarn will press upon pin 21, as is the condition shown in FIG. 2.

Pins 20 and 21 extend transversely to and are fixedly connected to lever arms 23 and 24 respectively. The connection may be formed by soldering, welding or by similar methods. The pins 20 and 21 are disposed in the vicinity of the slot 14 so that when the yarn 19 leaves the slot 14 at either of the two extreme positions shown in FIGS. 1 and 2 respectively, the yarn will contact the pin 20 and 21 respectively. When either of the pins are so contacted by the withdrawing yarn, the associated arm pivots and actuates the microswitch, 18 or 17 respectively, to which it is connected.

The microswitches 17 and 18, which are mounted on the apparatus housing 25 by screws 26 and 27 respectively are connected in a circuit containing a variable speed motor (not shown in FIGS. 1 to 3) the speed of which is controlled by the operation of the microswitches in accordance with the conducting state of the two microswitches in a manner which is described below.

Microswitch 17 is mounted in a horizontal position so that when the leading end of the head of the plug is in the position intermediate the extreme positions shown in FIGS. 1 and 2, that is when the yarn 19 is not contacting either of pins 20 or 21, the weight of the pin 21 acting upon the lever arm 24 will keep microswitch 17 normally in the on condition. Microswitch 18, however, is mounted at an upward angle of approximately 30 so that when the withdrawing yarn 19 is not contacting pin 20, the downward component of the weight of pin 20 will not be sufiicient to place microswitch 18 in the on position. Therefore, when the withdrawing yarn is intermediate the two extreme positions shown in FIGS. 1 and 2, switch 17 will be on and switch 18 will be off.

As shown in FIG. 2, when the withdrawing yarn 19 makes contact with pin 21, lever arm 23 is lifted, placing microswitch 17 into the OE position.

If the leading end or head of the plug is then caused, in a manner described below, to move forward within the passage, the yarn 19 moves out of contact with the pin 21, causing the lever arm 24 to fall to its rest position, thereby placing the top microswitch 17 in the on position.

As shown in FIG. 1, when the yarn 27 presses against the pin 20, lever arm 23 of bottom microswitch 18 is pressed downwardly to place microswitch 1 8 in the on" position. The leading end or head of the plug is then caused, in a manner described below, to move within the passage until the withdrawing yarn 19 moves away from pin 20 to allow switch 18 to once again come into the circuit.

The reaction of the pins 20 and 21 on the yarn when the yarn impinges the pins causes very little, if any, variation in tension in the withdrawing yarn. As the pins 20 and 21 are positioned to sense the withdrawing yarn the pins do not exert any back-pressure on the yarn plug.

FIG. 4 shows an electrical circuit by means of which the microswitches 17 and 18 can control the speed of operation of a two speed motor drivingly connected to the winding means (not shown) for the crimped yarn.

The microswitches 17 and 18 are connected in parallel with each other, and each microswitch has in series therewith an adjustable resistor 17a and 18a respectively. One side of each switch is connected by a lead 28 to one pole of a DO. supply 29. The other side of each of the switches is connected by a lead 30 to a solenoid coil 31 and thence to the other pole of the DC. supply 29.

Within the solenoid coil 31 is an armature 32 carrying a contact 33 at its lower end. The moveable contact 33 is associated with two fixed contacts 34 and 35, and is normally urged to close on to the contact 34 by means of a spring 36.

The winding of the solenoid coil 31 and the polarity of the DC. supply 29 are so arranged, that energisation of the coil 31 tends to move the armature to open the contacts 33, 34 against the action of the spring 36, and close the contacts 33, 35.

The contact 33 is connected to one side of an A.C. supply, and the contacts 34, 35 are connected in the circuit of a two-speed electric motor 35a which is drivingly connected to the winding means (not shown) for the crimped yarn, the motor being connected to the other side of the A.C. supply. The motor is provided with two setsof field windings 36a and 37a; one set actuating the motor at its higher speed, and the other at its lower speed. The contact 34 is connected to the slow speed field coil 37a, and the contact 35 is connected to the high speed field coil 36a, hence with the contacts 33, 35 closed the motor operates at its faster speed and with the contacts 33, 34 closed the motor operates at its slower speed.

In operation the switch 17 will be normally closed and the switch 18 will be normally open whilst the yarn I9 unravelling from the leading end of the yarn plug passes freely between the two switches. If the contacts 33, 34 are closed, so that the motor is running at its lower speed, a current will be flowing through the solenoid coil 31 via the switch 17. This current will, however, be arranged, by adjusting the resistor 17a, to be insufficient to move the armature 32 to open contacts 33, 34.

Due to the fact that the motor is running at its lower speed, the leading end of the plug of yarn 12 advances in the passage 11 until the yarn 19 leaving the slot 14 engages the pin 20 and closes the switch 18. An increased current will then flow through the solenoid coil 31, and the armature 32 will be caused to open the contacts 33, 34 and close the contacts 33, 35. The motor will now operate at its faster speed so that the yarn 19 will be wound more rapidly, the leading end of the plug 12 will move back in the passage 11, and the yarn 19 will move out of contact with pin 20 so that switch 18 will open. A reduced current will now flow through the solenoid coil 31 which is, however, sufficient to maintain the armature lifted against the action of spring 36 and retain the contacts 33, 35 engaged.

The motor will operate at its faster speed until the withdrawing yarn 19 moves back to the position shown in FIG. 2 and engages pin 21 to open switch 17. No current will then flow through coil 31, and the armature will be drawn down by spring 36 to re-engage contacts 33, 34 so that the motor once more operates at its slower speed and the yarn 19 disengages from the pin 21 to again close switch 17.

Hence it will be seen that by means of the circuit illustrated in FIG. 4 the rate of withdrawal of yarn from the crimping apparatus can be controlled by a two speed motor, so as to keep the leading end of the plug of crimped yarn between two predetermined spacial limits.

A circuit for controlling the rate of withdrawal of yarn by a three speed motor is shown in FIG. 5.

In this arrangement, when switch 17 is on and switch 18 is off, that is when the yarn is contacting neither pin, the motor operates at a normal operating speed. When both switches are on that is when the yarn 19 contacts pin 20, the motor is in a high-speed mode of operation. The third position is when the yarn 19 contacts pin 21 so that the switches are both in the of position and the motor is in a low-speed mode of operation.

In the circuit shown in FIG. 5 relays 37 and 38 are actuably connected to switches 17 and 18 respectively.

Connected to the field winding 39 of motor 40 are three resistors, 41, 42 and 43, each having a diiferent value of resistance. A relay contact system 44 is con- 7 trolled by the switches 17 and 18 and determines which of the three resistors will be in series with the field winding. The value of field current, and hence the motor speed, is thus seen to be a function of the positions of switches 17 and 18.

In operation, the withdrawing yarn 19 will first contact pin 21, causing the motor to be placed in the low speed mode of operation. The leading head or end of the plug will then continue to move around within the passage until the plug is in the position at which the withdrawing yarn will contact pin 20, causing the motor to operate at a higher speed, whereupon the leading end or head of the plug will retreat within the passage so that the yarn 19 will eventually move away from the pin 20.

In FIG. 6, the crimping and control means of the invention are schematically illustrated in combination with conventional winding means 50 in which a yarn take-up package is surface driven by a roller which in turn is driven by the motor M. Switch SW in this figure corresponds to the FIG. 4 switch comprised of contacts 33, 34 and 35 or to the relay contact system 44 of FIG. 5. The crimping and control elements of FIG. 6 and their operative arrangement are as hereinabove described. It is apparent that an increase or decrease in the speed of motor M increases or decreases, respectively, the rate of take-up of the yarn by the winding means 50.

Whereas two microswitches have been described above, it will be appreciated that a single microswitch may be used to control the withdrawal rate of the yarn. In such an arrangement "an actuating member is arranged to operate the switch only when the withdrawing yarn has moved beyond a predetermined limit. In order to give a similar mode of operation to the described embodiment the single microswitch can be arranged having either two separate actuating members, or, one actuating member having two limbs. When the withdrawing yarn moves towards and impinges one of the members, or one of the limbs, the switch is arranged to be switched to-say-- its on position and remain on until the withdrawing yarn impinges the other member, or limb, when the microswitch will be switched to the off position.

I claim:

1. An apparatus for crimping yarn including means for feeding the yarn into a passage, means for restricting the rate of travel of the yarn through the passage so that it is compressed along its length to form a plug of crimped yarn, means for drawing oil the crimped yarn from the leading end of the plug through an exit from the passage and in a direction such that the path of the Withdrawing yarn downstream from the plug varies in accordance with the position of the leading end of the plug, said means for drawing off including winding means, switch means operatively connected with said winding means, switch actuating means connected to said switch means and disposed be tween said exit from the passage and said winding means, said actuating means being so disposed with respect to said path of the withdrawing yarn that when the leading end of the plug moves beyond a limit of a predetermined position in the passage the withdrawing yarn assumes a path in which it causes said switch actuating means to actuate the switch means to vary the rate of drawing off the crimped yarn through said exit and thereby restore the leading end of the plug to said predetermined position.

2. An apparatus according to claim 1, wherein the means for restricting the rate of travel of the yarn through said passage comprises a wheel.

3. An apparatus according to claim 2, in which said wheel has a serrated peiphery.

4. An apparatus according to claim 3, wherein the periphery of said wheel projects into an arcuate groove in said passage which circles said wheel and along which groove the plug of crimped yarn travels with said wheel.

5. An apparatus according to claim 1, wherein said switch actuating means comprises a switch actuating member engageable by the withdrawing yarn, the switch actu- 8 t ating member being caused to move beyond a predetermined position of the member by engagement with the withdrawing yarn whenever the leading end of the plug moves beyond said limit so that the switch actuating member actuates the switch means to vary the rate of drawing off the crimped yarn.

6. An apparatus according to claim 5, wherein the switch actuating member is arranged to actuate said switch means whenever said member is caused to move beyond a second predetermined position displaced from the first mentioned predetermined position of the member, said a second predetermined position displaced from the first ment of the leading end of the plug of yarn in said passage beyond a second limit of its predetermined position, whereby the switch means is actuated to vary the rate of drawing off the yarn whenever the leading end of the plug moves beyond either the first mentioned or the second limit to thereby restore the leading end of the plug between these limits.

7. An apparatus'according to claim 1, wherein said switch means comprises first and second electrical switches, and said switch actuating means comprise first and second switch actuating members respectively connected to said first and second switches, said first and second actuating members being so located as to be impinged by the withdrawing yarn when the leading end of the plug is respectively positioned beyond predetermined forward and backward limits of its predetermined position in the passage, and thereby restore the leading end of the plug between said predetermined forward and backward limits.

8. An apparatus according to claim 7, including a variable speed electrical drive motor coupled to said winding means, and an electrical circuit for energising said motor, which circuit has connected therein said first and second switches arranged on operation to vary the energisation of the motor and hence its speed.

9. An apparatus according to claim 8, wherein the motor is a direct current motor and said first and second switches are arranged on operation to vary a supply of power to the field circuit of said motor.

10. An apparatus according to claim 7, wherein the electrical circuit includes two different energising circuits for causing the motor to rotate at a high speed and a slow speed, the first and second switches being arranged on operation to change the speed of the motor from the slow speed to the high speed and from the high speed to the slow speed respectively.

11. An apparatus according to claim 7, wherein the electrical circuit includes three energising circuits for causing the motor to rotate at three respective speeds, the motor being rotated at a high speed when the withdrawing yarn impinges said first actuating member, a low speed when the yarn impinges said second actuating member and otherwise at an intermediate speed.

12. An apparatus for crimping yarn including means for feeding the yarn into a grooved arcuate passage, a serrated wheel for restricting the rate of travel of the yarn through the passage so that the yarn is compressed along its length to form a plug of crimped yarn, the plug of crimped yarn travelling in the groove in the passage with said wheel, win-ding means for drawing off the crimped yarn from the leading end of the plug through an exit from said passage and in a direction generally transverse to the direction of movement of the leading end of the plug, switch means operatively connected with said winding means, switch actuating means connected to said switch means and being so located with respect to said exit that when the leading end of the plug moves :beyond a predetermined limit in the passage the withdrawing yarn impinges said switch actuating means to actuate the switch means to vary the rate of rotation of the winding means and thereby restore the position of the leading end of the plug within said predetermined limit.

13. A method of crimping yarn comprising feeding yarn into a passage to form a plug, engaging the plug of 9 10 yarn and conveying the plug towards an exit of the References Cited passage, withdrawing the yarn from the leading end of UNITED STATES PATENTS the plug in a direction generally transverse to the direction 3,153,837 10/1964 schippers et alof movement of the leading end of the plug as it is being conveyed whereby the path of the withdrawing yarn 5 3174206 3/1965 Mattmgly et downstream from the plug varies in accordance with the position of the leading end of the plug, sensing variations LOUIS RIMRODT Primary Examiner of said path beyond predetermined limits, and controlling U 5 C1 X R the rate of withdrawal of the yarn in response to said I I sensed variations to maintain the leading end of the plug 10 in the passage within predetermined limits. 

